CVE-2026-43376 is a critical use-after-free vulnerability in the Linux kernel's ksmbd component. The flaw arises because oplock_info structures are freed immediately without waiting for RCU grace periods, leading to potential access of freed memory. This can cause memory corruption and severe impacts on confidentiality, integrity, and availability. The issue is fixed by deferring the freeing of oplock_info using call_rcu().